Propulsion
The word propulsion is derived from two Latin words:
pro meaning before or forward pellere meaning to push or drive.
• Propulsion means to push or drive forward an object.

Mechanics
• Motion (displacement, velocity, acceleration)
What causes motion or changes motion?
• Force (momentum)
Why do some objects accelerate more than others?
Newton termed the momentum of a body as the quantity of motion.
• Work
• Energy
• Power